Add emulation of SAVE16 and RESTORE.JRC16 instructions. Routines
gen_save(), gen_restore(), and gen_adjust_sp() are provided to support
this feature.
This patch at the same time provides function gen_op_addr_addi(). This
function will be used in emulation of some other nanoMIPS instructions.
Backports commit bf0718c59a4b27dd01346a7b5b9a183ed1b18fb7 from qemu
Add empty body and invocation of decode_nanomips_opc() if the bit
ISA_NANOMIPS32 is set in ctx->insn_flags.
Backports commit c533c0f4741be62501ef6c7f6ce77ffbfc2e4964 from qemu
Only if Config3.ISA is 3 (microMIPS), the mode should be switched in
cpu_state_reset(). Config3.ISA is 1 for nanoMIPS processors, and no mode
change should happen.
Backports commit 0bbc0396809f6caaaf96863dafe738e94f9b73ea from qemu
Add nanoMIPS opcodes. nanoMIPS instruction are organized by so-called
instruction pools. Each pool contains a set of opcodes, that in turn
can be instruction opcodes or instruction pool opcodes.
Backports commit 261c95a0e98e5e9b13c9c005a991b7e7dc27f38a from qemu
MFHC0 and MTHC0 used to handle EntryLo0 and EntryLo1 registers only,
and placing ELPA flag checks before switch statement were technically
correct. However, after adding handling more registers, these checks
should be moved to act only in cases of handling EntryLo0 and
EntryLo1.
Backports commit 59488dda1f16c0259bc2610d8d71686ef436c649 from qemu
Fix two instances of shadow variables. This cleans up entire file
translate.c from shadow variables.
Backports commit e1555d7ddf2c86fb92165e47eb092f1f5fa9e8bd from qemu
Mark switch fallthroughs with comments, in cases fallthroughs
are intentional.
The comments "/* fall through */" are interpreted by compilers and
other tools, and they will not issue warnings in such cases. For gcc,
the warning is turnend on by -Wimplicit-fallthrough. With this patch,
there will be no such warnings in target/mips directory. If such
warning appears in future, it should be checked if it is intentional,
and, if yes, marked with a comment similar to those from this patch.
The comment must be just before next "case", otherwise gcc won't
understand it.
Backports commit 146dd620db815558938433eb9f57a571d424d2c6 from qemu
Remove "range style" case statements to make code analysis easier.
This patch handles cases when the values in the range in question
were not properly defined.
Backports commit c38a1d52233c85976eeed99c9015e881de8cd68e from qemu
Remove "range style" case statements to make code analysis easier.
This is needed also for some upcoming nanoMIPS-related refactorings.
Backports commit c2e19f3c2b1a1bb5f4fc3c55ee8cfa28dde9b810 from qemu
Offset can be larger than 16 bit from nanoMIPS,
and immediate field can be larger than 16 bits as well.
Backports commit 72e1f16f18fe62504f8f25d7a3f6813b24b221be from qemu
Do the cast to uintptr_t within the helper, so that the compiler
can type check the pointer argument. We can also do some more
sanity checking of the index argument.
Backports commit 07ea28b41830f946de3841b0ac61a3413679feb9 from qemu
Notes:
- DISAS_TOO_MANY replaces the former "break" in the translation loop.
However, care must be taken not to overwrite a previous condition
in is_jmp; that's why in translate_insn we first check is_jmp and
return if it's != DISAS_NEXT.
- Added an assert in translate_insn, before exiting due to an exception,
to make sure that is_jmp is set to DISAS_NORETURN (the exception
generation function always sets it.)
- Added an assert for the default case in is_jmp's switch.
Backports commit 18f440edfb974feaff8490d4861844b5a2b7a3b5 from qemu
No changes to the logic here; this is just to make the diff
that follows easier to read.
While at it, remove the unnecessary 'struct' in
'struct TranslationBlock'.
Note that checkpatch complains with a false positive:
ERROR: space prohibited after that '&' (ctx:WxW)
\#75: FILE: target/mips/translate.c:20220:
+ ctx->kscrexist = (env->CP0_Config4 >> CP0C4_KScrExist) & 0xff;
^
Backports commit 12be92588cf26a192f1b62846906983fc1e102a7 from qemu
Notes:
- BS_EXCP in generate_exception_err and after hen_helper_wait
becomes DISAS_NORETURN, because we do not return after
raising an exception.
- Some uses of BS_EXCP are misleading in that they're used
only as a "not BS_STOP" exit condition, i.e. they have nothing
to do with an actual exception. For those cases, define
and use DISAS_EXIT, which is clearer. With this and the
above change, BS_EXCP goes away completely.
- fix a comment typo (s/intetrupt/interrupt/).
Backports commit b28425babc2ad4b90cd87d07a1809d3322b9c065 from qemu
The TB after BS_STOP is not fixed (e.g. helper_mtc0_hwrena
changes hflags, which ends up changing the TB flags via
cpu_get_tb_cpu_state). This requires a full lookup (i.e.
with flags) via lookup_and_goto_ptr instead of gen_goto_tb,
since the latter only looks at the PC for in-page goto's. Fix it.
Backports commit cd314a7d0190a03122ca0606ecf71b4b873a22c6 from qemu.
If the PC is in the last page of the address space, next_page_start
overflows to 0. Fix it.
Backports commit 6cd79443d33e6ba6b4c5b787eb713ca1cec56328 from qemu
Rather than have a separate buffer of 10*max_ops entries,
give each opcode 10 entries. The result is actually a bit
smaller and should have slightly more cache locality.
Backports commit 75e8b9b7aa0b95a761b9add7e2f09248b101a392 from qemu
It is unlikely that we will ever want to call this helper passing
an argument other than the current PC. So just remove the argument,
and use the pc we already get from cpu_get_tb_cpu_state.
This change paves the way to having a common "tb_lookup" function.
Backports commit 7f11636dbee89b0e4d03e9e2b96e14649a7db778 from qemu
now cpu_mips_init() reimplements subset of cpu_generic_init()
tasks, so just drop it and use cpu_generic_init() directly.
Backports commit c4c8146cfd0fc3f95418fbc82a2eded594675022 from qemu
Register separate QOM types for each mips cpu model,
so it would be possible to reuse generic CPU creation
routines.
Backports commit 41da212c9ce9482fcfd490170c2611470254f8dc from qemu
This changes the order between cpu_mips_realize_env() and
cpu_exec_initfn(), but cpu_exec_initfn() don't have anything that
depends on cpu_mips_realize_env() being called first.
Backports commit df4dc10284e1d871db8adb512816a561473ffe3e from qemu
no logical change, only code movement (and fix a comment typo).
Backports commit 26aa3d9aecbb6fe9bce808a1d127191bdf3cc3d2 from qemu
Also backports commit 5502b66fc7d0bebd08b9b7017cb7e8b5261c3a2d
RDHWR CC reads the CPU timer like MFC0 CP0_Count, so with icount enabled
it must set can_do_io while it calls the helper to avoid the "Bad icount
read" error. It should also break out of the translation loop to ensure
that timer interrupts are immediately handled.
Backports commit d673a68db6963e86536b125af464bb6ed03eba33 from qemu
DMTC0 CP0_Cause does a redundant gen_io_start() and gen_io_end() pair,
even though this is done for all DMTC0 operations outside of the switch
statement. Remove these redundant calls.
Backports commit 51ca717b079dccae5b6cc9f45153f5044abd34f0 from qemu
Commit e350d8ca3ac7 ("target/mips: optimize indirect branches") made
indirect branches able to directly find the next TB and jump straight to
it without breaking out of translated code and going around the main
execution loop. This breaks the assumption in target/mips/translate.c
that BS_STOP is sufficient to cause pending interrupts to be handled,
since interrupts are only checked in the main loop.
Fix a few of these assumptions by using gen_save_pc to update the saved
PC and using BS_EXCP instead of BS_STOP:
- [D]MFC0 CP0_Count may trigger a timer interrupt which should be
immediately handled.
- [D]MTC0 CP0_Cause may trigger an interrupt (but in fact translation
was only even being stopped in the DMTC0 case).
- [D]MTC0 CP0_<any> when icount is used is assumed could potentially
cause interrupts.
- EI may trigger an interrupt which was pending. I specifically hit
this case when running KVM nested in mipsel-softmmu. A timer
interrupt while the 2nd guest was executing is caught by KVM which
switches back to the normal Linux exception base and re-enables
interrupts with EI. Since the above commit QEMU doesn't leave
translated code until the nested KVM has already restored the KVM
exception base and returned to the 2nd guest, at which point it is
too late to check for pending interrupts and it gets stuck in an
infinite loop of unhandled interrupts.
Something similar was needed for ARM in commit b29fd33db578
("target/arm: use DISAS_EXIT for eret handling").
Backports commit b74cddcbf6063f684725e3f8bca49a68e30cba71 from qemu
Writing to the MIPS DESAVE register (and now the KScratch registers)
will stop translation, supposedly due to risk of execution mode
switches. However these registers are basically RW scratch registers
with no side effects so there is no risk of them triggering execution
mode changes.
Drop the bstate = BS_STOP for these registers for both mtc0 and dmtc0.
Backports commit cb539fd241900f51de7d21244f7a55422ad0d40a from qemu
The optional segmentation control registers CP0_SegCtl0, CP0_SegCtl1 &
CP0_SegCtl2 control the behaviour and required privilege of the legacy
virtual memory segments.
Add them to the CP0 interface so they can be read and written when
CP0_Config3.SC=1, and initialise them to describe the standard legacy
layout so they can be used in future patches regardless of whether they
are exposed to the guest.
Backports commit cec56a733dd2c3fa81dbedbecf03922258747f7d from qemu
The MIPS mmu_idx is sometimes calculated from hflags without an env
pointer available as cpu_mmu_index() requires.
Create a common hflags_mmu_index() for the purpose of this calculation
which can operate on any hflags, not just with an env pointer, and
update cpu_mmu_index() itself and gen_intermediate_code() to use it.
Also update debug_post_eret() and helper_mtc0_status() to log the MMU
mode with the status change (SM, UM, or nothing for kernel mode) based
on cpu_mmu_index() rather than directly testing hflags.
This will also allow the logic to be more easily updated when a new MMU
mode is added.
Backports commit b0fc6003224543d2bdb172eca752656a6223e4a1 from qemu
Implement decoding of microMIPS EVA load and store instruction groups in
the POOL31C pool. These use the same gen_ld(), gen_st(), gen_st_cond()
helpers as the MIPS32 decoding, passing the equivalent MIPS32 opcodes as
opc.
Backports commit 8fffc64696783b1ff1d17262d098976479895660 from qemu
Add CP0.ErrCtl register with WST, SPR and ITC bits. In 34K and interAptiv
processors these bits are used to enable CACHE instruction access to
different arrays. When WST=0, SPR=0 and ITC=1 the CACHE instruction will
access ITC tag values.
Generally we do not model caches and we have been treating the CACHE
instruction as NOP. But since CACHE can operate on ITC Tags new
MIPS_HFLAG_ITC_CACHE hflag is introduced to generate the helper only when
CACHE is in the ITC Access mode.
Backports commit 0d74a222c27e26fc40f4f6120c61c3f9ceaa3776 from qemu
Implement decoding of MIPS32 EVA loads and stores. These access the user
address space from kernel mode when implemented, so for each instruction
we need to check that EVA is available from Config5.EVA & check for
sufficient COP0 privilege (with the new check_eva()), and then override
the mem_idx used for the operation.
Unfortunately some Loongson 2E instructions use overlapping encodings,
so we must be careful not to prevent those from being decoded when EVA
is absent.
Backports commit 7696414729b2d0f870c80ad1dd637d854bc78847 from qemu
EVA load and store instructions access the user mode address map, so
they need to use mem_idx of MIPS_HFLAG_UM. Update the various utility
functions to allow mem_idx to be more easily overridden from the
decoding logic.
Specifically we add a mem_idx argument to the op_ld/st_* helpers used
for atomics, and a mem_idx local variable to gen_ld(), gen_st(), and
gen_st_cond().
Backports commit dd4096cd2ccc19384770f336c930259da7a54980 from qemu
